What is an eSIM? What it means for your phone or Apple Watch

Put simply, eSIM, or embedded SIM card, replaces the need for a physical SIM card - and therefore, a SIM card slot - on your device. While the number of devices using it has remained relatively humble, with Apple's iPhone 14 and iPhone 14 Pro making the jump to eSIM-only in the US, it's only a matter of time before other smartphone manufacturers follow suit.

Source : https://www.pocket-lint.com/what-is-an-esim-and-how-will-it-change-connected-devices-for-the-better/